Friday, August 3, 2012

Simple Antennas for the Amateur Radio Operator--a continuing series

KH6JRM's Amateur Radio Blog

Post #179

Portable antennas for the unexpected

I've made it a habit over the past few years to keep an emergency "go" kit in my van in case I'm needed to provide communications backup for our local civil defense agency and the Hilo office of the American Red Cross.  Other than the 11 March 2011 tsunami (the one that damaged Japan and its Fukushima nuclear reactor), I haven't used my portable equipment that much, except for weekend operations in a local park or beach area.  When I worked at Pacific Radio Group, I kept an old Kenwood TS-520 and a Kenwood HT at the station for emergency backup to the Hawaii County Civil Defense office in Hilo.  But, since I retired, my forays into portable operation have been subject to personal whim or to opportunities I get handed to me.

Such is the case this weekend, where I revert to my 22nd year as the tower announcer for the Big Island Auto Club's monthly points meets.  I'm under contract to provide weekend drag race coverage for my former employer, as well as coverage during primary and general elections.  The work is part-time, which suits me fine.

Anyway, the track manager and I usually arrive at the track at around 0500 W to help the maintenance crew prepare the track for the races, which begin around 1100 W.  Since my work in the tower is fairly basic (turn on the generator, hook up the race computers, test the timing lights, and make sure track HTs are charged and working), I usually have a few hours of free time to explore amateur radio in a quiet zone just outside of Hilo town.  There are no power lines near the track, so all track power is produced locally by a state of the art diesal generator.  The track is very  quiet radio-wise until the race cars arrive--then you must put on ear protection to ward off the din of noise associated with drag racing.

As I've done in past races, I usually set up a mobile antenna on an adjoining chain link fence, run out several radials, and connect the arrangement to my trusty Drake MN-4 tuner with about 50-feet of 450-ohm ladder line.  Currently, I'm using a 54-inch Hustler mast with 40 and 20 meter loading coils.  The low-power Yaesu FT-7 provides the signal.  The early morning conditions shortly before sunrise are quite good on 40 meters.

When the track closes down after sunset, the clean up and lockdown of the track begins.  This task takes about two hours, depending on whether oil has spilled on the track or lights/sensors have to be repaired.  Tower clean up takes only about 30 minutes--mostly disconnecting computers and securing timing equipment in a secure area.  That gives me around 1.5 hours to have some fun on 40 and 20 meters shortly after sundown.  Once again, the same arrangement is used.  Results have been good on most race nights.  This schedule also gives me time to check out weak links in my own equipment and to improve the antennas.

Some of my fellow race fans have expressed interest in amateur radio after they see the system I bring with me on race days.  Perhaps, I'm having a good influence afterall.  I'm an old "gearhead" anyway, so any chance I get to combine radio and racing is an open invitation to explore new antennas and create a little "buzz" for amateur radio.

This will be a busy weekend, so it's off to the futon and a few hours of sleep before I drive through the pre-dawn mist to the Hilo Drag Strip.

Have a productive and safe weekend!

Aloha es 73 de KH6JRM--BK29jx15